Question: when is the {start time} for {Joseph-Louis Lagrange} who {member of} as {Prussian Academy of Sciences} ?
Paraphrase: When did Joseph-Louis Lagrange become a member of the Prussian Academy of Sciences?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q80222 p:P463 ?s . ?s ps:P463 wd:Q329464 . ?s pq:P580 ?value}